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or installing new CHP systems as a natural gas option. Not surprisingly, PUCO makes a strong pitch for CHP as the best choice, touting efﬁ ciency performance beneﬁ ts of 65–80%, plus lower operating costs and lower environmental impact. For those skeptical of the claims, a look at the success of CHP at the University of Cincinnati in Ohio can be an educational experience. Between the campus and six hospitals, the two utility pro-duction plants at University of Cincinnati (UC) serve about 100 buildings. A pair of 12.5-MW Titan 130 Gas Turbine Generators from Solar Turbines, a division of Caterpillar, Peo-ria, IL, plus a 20-MW steam turbine generator provide about 90% of the electricity demands of the campus, and 80,000 pph of unﬁ red steam for both heating and cooling. All told, the plant attains a 70% efﬁ ciency rating. Not surprisingly, UC’s distributed energy system has earned awards from EPA for its environmental impact and from the DOE for its efﬁ ciency performance. microgrid model for facilities, including locations that are either community scale, or sized for facilities such as corporate parks, sports centers, and, of course, educational institutions. It’s efforts such as IIT’s that lead the number crunch-ers at Pike Research to predict a bright future for microgrids. The company’s researchers expect that annual vendor rev-enues from utility microgrids, public power grid-tied, and remote microgrids will grow to just under $3.3 billion in 2018. According to Pike senior research analyst Peter Asmus, market drivers include information technology (IT) advances, sophis-ticated software, and new islanding inverters for (mostly) cleaner renewable generation-to-network resources. More-over, decades of utility resistance to the concept of microgrids are falling as conﬁ dence in the beneﬁ ts grows. Conﬁ dence is high at GE, Fairﬁ eld, CT, and the company recently released its Multilin Microgrid Control System designed to help per-manently islanded or grid-connected microgrid operators integrate renewable energy and fossil fuel-based resources to optimize microgrid operations and minimize energy costs. Avoiding Utility Tariffs According to Juan Macias, general manager, Grid Automation There’s been no official award for the financial benefits, but for GE’s Digital Energy business, the demand is growing from they are equally impressive, according to Joe Harrell, execu-sources such as military installations, and various institutions seeking options to maximize energy use. tive director of Central Utilities at UC. Harrell notes that just For a compelling demonstration of utility cooperation and the free steam alone saves UC $2,590,000 per year. And the conﬁ dence from state energy agencies we can look to the Uni-electricity plant’s peak shaving capabilities save even more; versity of California San Diego (UCSD), where the California under the PJM utility formula of tariff demand rates are set Energy Commission (CEC) based on the summer peak recently approved funding from the highest of 3,096, to advance development of 15-minute intervals. So a pioneering microgrid and what’s that mean for the bot-expand electric vehicle charg-tom line? One bad 15-minute ing resources. The campus has period could cost UC over two 13.5-MW Solar Turbines $6,100,000 in demand and generating about 27 MW of ratchet fees. And finally, the electricity, then there’s an savings from reliability must additional 3-MW steam tur-be considered, especially with bine. The entire CHP system two hospitals and their sensi-produces 140 MMBtu per tive electronics. So far, UC hour of steam to satisfy 95% has logged a 99.98% energy of campus thermal demand. reliability rating. At efﬁ ciency levels of 66%, the Blackout and power Paralleling switchgear at Columbus Regional Healthcare runs routine power system uses 26% less fuel than interruptions are costly for system testing and energy management during peak periods. your average onsite thermal universities. For example, at generation and purchased the Illinois Institute of Tech-electricity. The university reports that its power plant saves nology (IIT), the campus suffered 12 power outages during 2004–2006, accounting for substantial losses in damaged hard-about $670,000 per month in energy costs. Additional savings come from renewable energy resources. The campus also hosts ware, compromised research, expenses for alternative student a 1.2-MW photovoltaic (PV) system and a 2.8-MW fuel cell housing, and more. The solution was a partnership with the plant fueled by methane from a wastewater treatment plant, DOE to build a $13 million microgrid. The system is based on plus a 300-kW solar water heating system. smart switches for enhancing reliability, rooftop solar panels, As a microgrid, the system can run securely by discon-wind generation units, ﬂ ow batteries, and charging for electric necting from parallel operations with the grid to run indepen-vehicles), and it’s all networked to smart buildings (equipped dently in “island mode.” This beneﬁ t proved invaluable during with campus and building controllers). a disastrous countywide ﬁ re in 2007, when UCSD was able to The microgrid can be operated as a standalone power disengage from drawing 3 MW from the local utility SDG&E system during grid failures, and administrators estimate that and, within 30 minutes, begin exporting about 4 MW of excess the campus saves about $1 million dollars per year in electric-power to bolster the grid’s failing assets. ity costs and damages linked to blackouts. The good news Such beneﬁ ts haven’t gone unnoticed by the CEC. for other facility managers is that IIT’s Galvin Center leader-Starting with an initial investment of $4 million in 2008, ship is actively working with interested parties to replicate its MTU Distributed Energy May 2013 39